Posts tagged: Remote Access Trojan

An emerging malware threat identified as the Duqu trojan has received a great deal of attention because it is similar to the infamous Stuxnet worm of 2010.

What is Duqu?
The Duqu trojan is composed of several malicious files that work together for a malicious purpose. The first component is a Windows kernel driver that searches for and loads encrypted dynamic link library (DLL) files. The decrypted DLL files implement the main payload of Duqu, which is a remote access trojan (RAT). The RAT allows an adversary to gather information from a compromised computer and to download and run additional programs.

The facts observed through software analysis are inconclusive in terms of proving a direct relationship between Duqu and Stuxnet at any other level.

Does Duqu target industrial control systems?
Unlike Stuxnet, Duqu does not contain specific code that pertains to supervisory control and data acquisition (SCADA) components such as programmable logic controllers (PLCs). Duqu’s primary purpose is to provide an attacker with remote access to a compromised computer, including the ability to run arbitrary programs. It can theoretically be used to target any organization.

Is there any evidence in the code indicating specific targets?
Duqu facilitates an adversary’s ability to gather intelligence from an infected computer and the network. Any specific market segments, technologies, organizations or countries that are targeted by the Duqu malware have not yet identified.

What are indicators of a Duqu infection?
The Duqu trojan attempts to use the network to communicate with a remote command and control (C2) server to receive instructions and to exfiltrate data. Analysis of Duqu revealed that it uses the 206.183.111.97 IP address as its C2 server. This IP address is located in India and has been shut down by the hosting provider. Also, Duqu may attempt to resolve the kasperskychk.dyndns.org domain name. The resulting IP address is not used for communications, so this lookup may serve as a simple Internet connectivity check. Administrators should monitor their network for systems attempting to resolve this domain or connect to the C2 IP address for possible infection.

The byproducts in Table 2 have been collected from multiple Duqu variants and would not be present on a single infected computer.

Name

File Size

MD5

jminet7.sys

24,960 bytes

0eecd17c6c215b358b7b872b74bfd80

netp191.pnf

232,448 bytes

b4ac366e24204d821376653279cbad8

netp192.pnf

6,750 bytes

94c4ef91dfcd0c53a96fdc387f9f9c3

cmi4432.sys

29,568 bytes

4541e850a228eb69fd0f0e924624b24

cmi4432.pnf

192,512 bytes

0a566b1616c8afeef214372b1a0580c

cmi4464.pnf

6,750 bytes

e8d6b4dadb96ddb58775e6c85b10b6c

<unknown>(sometimes referred to as keylogger.exe)

85,504 bytes

9749d38ae9b9ddd81b50aad679ee87e

nfred965.sy

24,960 bytes

c9a31ea148232b201fe7cb7db5c75f5

nred961.sys

unknown

f60968908f03372d586e71d87fe795c

adpu321.sy

24,960 bytes

3d83b077d32c422d6c7016b5083b9fc

iaStor451.sys

24,960 bytes

bdb562994724a35a1ec5b9e85b8e054f

The name “Duqu” was assigned to this malware because the keylogger program creates temporary files that begin with the prefix “~DQ”. A computer infected with Duqu may have files beginning with “~DQ” in Windows temporary directories.

How do Duqu infections occur?
The mechanism by which Duqu infections occur is unknown. Current analysis of Duqu has not revealed any ability to infect additional systems like the Stuxnet worm could.

Is antivirus and antimalware protection sufficient for detecting Duqu?
Since its discovery, security vendors have worked to improve their ability to detect Duqu. However, the author may simply release newer variants that are no longer detected by antivirus and antimalware products.

BlackHole is a variant of a well-known Remote Access Trojan (RAT) for Windows known as darkComet.

“Hello, Im the BlackHole Remote Administration Tool.
I am a Trojan Horse, so i have infected your Mac Computer.
I know, most people think Macs can’t be infected, but look, you ARE Infected!
I have full controll over your Computer and i can do everything I want, and you can do nothing to prevent it.
So, Im a very new Virus, under Development, so there will be much more functions when im finished.
But for now, it’s okay what I can do?”

This message, displayed in the full screen window with the reboot button blocks user’s screen.

As even the malware itself admits, it is not yet finished, but it could be indicative of more underground programmers taking note of Apple’s increasing market share.

Functions :

Remote execution of shell commands.

Opens URL using victim’s default browser.

Sends a message which is displayed on the victims screen.

Creates a text file.

Perform shutdown, restart and sleep operation.

Popping up a fake “Administrator Password” window to phish the target.